Medial Patellofemoral Ligament Reconstruction for Knee Dislocation

(SHYFT Trial)

Overseen By Sarah Kerslake, BPhty

Age: < 65

Sex: Any

Trial Phase: Academic

Sponsor: Banff Sport Medicine Foundation

Disqualifiers: Trochlear dysplasia, Osteoarthritis, Pregnancy, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Approved in 3 Jurisdictions This treatment is already approved in other countries

Compensation: Varies

Number of Visits: 6

Duration: Immediate post-operative period

32 Participants Needed

Trial Summary

What is the purpose of this trial?

The aim of this study is to investigate the role of tibial tubercle osteotomy (TTO) on the subjective and objective outcomes following medial patellofemoral ligament reconstruction (MPFL-R) in patients with an increased tibial tubercle-trochlear groove (TT-TG) distance with or without patella alta. This Pilot RCT will assess the feasibility of conducting this study for: 1. The ability to recruit study patients 2. Adherence to the study protocol 3. Completion rates of patient follow-up at a minimum of 12 months post-operative

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the trial coordinators or your doctor.

What data supports the effectiveness of the treatment Medial patellofemoral ligament reconstruction for knee dislocation?

Research shows that medial patellofemoral ligament (MPFL) reconstruction is commonly used to treat recurrent patellar dislocation, which is when the kneecap frequently slips out of place. Although there are reports of complications and failures, it remains a popular choice for addressing patellofemoral instability, especially in younger patients. ^{1 2 3 4 5}

Is medial patellofemoral ligament reconstruction generally safe for humans?

Medial patellofemoral ligament reconstruction is generally considered a reliable procedure, but it has a complication rate of up to 26%, including issues like recurrent instability and knee pain. Errors during surgery can also lead to problems, so it's important to have an experienced surgeon. ^{3 4 6 7 8}

How is medial patellofemoral ligament reconstruction different from other treatments for knee dislocation?

Medial patellofemoral ligament reconstruction is a unique surgical technique specifically designed to address recurrent patellar instability and dislocation by reconstructing the ligament that helps stabilize the kneecap. Unlike other treatments, it focuses on restoring the natural anatomy and biomechanics of the knee, which can be particularly beneficial for patients with repeated dislocations. ^{1 2 3 5 9}

Research Team

Laurie A Hiemstra, MD, PhD

Principal Investigator

University of Calgary

Eligibility Criteria

This trial is for young people aged 13-30 with recurrent knee cap dislocation and specific bone alignment issues (TT-TG ≥15mm on MRI or ≥18mm on CT). They must have mature bones, confirmed by x-rays. It's not for those with certain knee ratios, excessive femoral or tibial rotation, severe groove deformities needing surgery, advanced arthritis in the kneecap joint, cartilage restoration procedures, inability to do computer questionnaires or if pregnant.

Inclusion Criteria

TT-TG ≥15mm measured on MRI or ≥18mm on CT scan

I am between 13 and 30 years old.

My kneecap frequently dislocates causing pain.

Exclusion Criteria

I have moderate to severe knee arthritis confirmed by an X-ray.

Caton-Deschamps ratio ≥ 1.4 on lateral radiographs

Femoral anteversion ≥ 25 degrees on diagnostic imaging rotational profile

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo either isolated MPFL-R or MPFL-R with TTO surgery

Immediate post-operative period

Follow-up

Participants are monitored for safety and effectiveness after treatment, with assessments at 6, 12, and 24 months post-operative

24 months

Multiple visits at 6, 12, and 24 months post-operative

Long-term Follow-up

Participants continue to be monitored for long-term outcomes and complications

Beyond 24 months

Treatment Details

Interventions

• Medial patellofemoral ligament reconstruction

Trial Overview The study tests whether adding a bone realignment procedure (tibial tubercle osteotomy) to a ligament reconstruction surgery improves outcomes in patients with misaligned knees causing instability. This pilot randomized controlled trial will check how feasible it is to recruit participants and follow them up at least one year after surgery.

Participant Groups

Group I: MPFL-R Active Control 1 Intervention

Medial patellofemoral ligament reconstruction

Group II: MPFL-R + TTO Active Control 2 Interventions

Medial patellofemoral ligament reconstruction with concomitant tibial tubercle osteotomy

Medial patellofemoral ligament reconstruction is already approved in European Union, United States, Canada for the following indications:

Approved in European Union as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Approved in United States as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Approved in Canada as MPFL reconstruction for:

• Patellar instability
• Recurrent patellar dislocation

Who Is Running the Clinical Trial?

Banff Sport Medicine Foundation

Lead Sponsor

Trials

4

Recruited

160+

ConMed Corporation

Industry Sponsor

Trials

9

Recruited

800+

CONMED Corporation

Industry Sponsor

Trials

11

Recruited

1,100+

Canadian Orthopaedic Foundation

Collaborator

Trials

15

Recruited

1,900+

Findings from Research

In a study of 26 patients who experienced patellar redislocation after MPFL reconstruction, 69% of the cases were nontraumatic, indicating that underlying anatomical risk factors may play a significant role in these failures.

Half of the patients had nonanatomic femoral tunnel positions, and 65% had two or more anatomical risk factors, such as trochlear dysplasia and valgus malalignment, suggesting that careful preoperative assessment and precise surgical technique are crucial for successful outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Failure Analysis in Patients With Patellar Redislocation After Primary Isolated Medial Patellofemoral Ligament Reconstruction. Feucht, MJ., Mehl, J., Forkel, P., et al.[2022]

A novel MRI technique was developed to measure the distance from the Schöttle point to the medial distal femoral physis in 34 skeletally immature patients with patellar instability, revealing an average distance of 7.27 mm, which is crucial for safe MPFL reconstruction.

The study found that the Schöttle point is consistently located distal to the medial distal femoral physis, and females were closer to the Schöttle point than males, suggesting that surgical planning may need to account for these anatomical differences to avoid complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A Simple Method of Measuring the Distance From the Schöttle Point to the Medial Distal Femoral Physis With MRI. Bishop, ME., Black, SR., Nguyen, J., et al.[2022]

MPFL reconstruction is a new surgical method aimed at treating recurrent patellar instability and dislocation, but the radiologic outcomes post-surgery are not well documented in current literature.

The study reviews the anatomy and biomechanics of the MPFL and highlights imaging findings and potential complications following double-bundle MPFL reconstruction, emphasizing the need for better understanding of post-operative results.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MRI evaluation and complications of medial patellofemoral ligament reconstruction. Torabi, M., Wo, S., Vyas, D., et al.[2022]

In a study of 19 young patients who underwent revision surgery after unsuccessful medial patellofemoral ligament (MPFL) reconstruction, the main reasons for failure included not addressing additional risk factors, technical errors during surgery, and poor patient selection.

Post-revision, patients showed significant improvements in knee function and satisfaction, with median Kujala scores rising from 57 to 83 and 78.9% reporting satisfaction, indicating that revision surgery can be effective despite initial complications.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Analysis of failure and clinical outcome after unsuccessful medial patellofemoral ligament reconstruction in young patients. Nelitz, M., Williams, RS., Lippacher, S., et al.[2022]

In a study of 65 patients undergoing MPFL reconstruction for recurrent patellar dislocation, there were no reported episodes of dislocation or subluxation after surgery, indicating high effectiveness of the procedure.

Patients showed significant improvements in knee function, with Lysholm scores increasing from 60.6 to 89.8, Tegner scores from 3.6 to 5.6, and IKDC scores from 40.0 to 82.0, demonstrating both safety and efficacy of the surgical intervention.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Reconstruciton of medial patellofemoral ligament (MPFL) for the treatment of recurrent patellar dislocation]. Yun, XD., Xia, YY., Wu, M., et al.[2022]

The study identified the most isometric attachment point for medial patellofemoral ligament (MPFL) reconstruction, which is located posterior and proximal to the anatomic femoral MPFL attachment, showing only a 4% length change during knee flexion.

It was found that improper positioning of MPFL tunnels, particularly proximal and anterior placements, can lead to significant changes in ligament length during movement, emphasizing the need for precise graft placement to reduce complications like recurrent instability.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The Medial Patellofemoral Ligament Is a Dynamic and Anisometric Structure: An In Vivo Study on Length Changes and Isometry. Kernkamp, WA., Wang, C., Li, C., et al.[2020]

The medial patellofemoral ligament (MPFL) is crucial for knee stability, and its reconstruction (MPFLR) is recommended primarily for patients with a history of multiple patellar dislocations after conservative treatments fail.

Current literature lacks definitive comparisons of surgical techniques for MPFLR, making it essential to carefully evaluate candidates to minimize risks and ensure effective outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

MPFL reconstruction: indications and results. Dall'Oca, C., Elena, N., Lunardelli, E., et al.[2023]

MPFL reconstruction effectively reduces lateral tracking of the patella, which is important for preventing instability, but errors in femoral fixation and graft tension can lead to overcorrection and increased pressure on the medial patellar cartilage.

Simulations showed that nonanatomic femoral attachment and decreased graft length resulted in significant increases in medial pressures, indicating that precise surgical techniques are crucial to avoid complications such as loss of knee flexion and cartilage overload.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Dynamic Simulation of the Effects of Graft Fixation Errors During Medial Patellofemoral Ligament Reconstruction. Elias, JJ., Kelly, MJ., Smith, KE., et al.[2020]

In a study of 23 patients undergoing MPFL reconstruction for recurrent patellar dislocation, no recurrences were reported, indicating the procedure's efficacy in preventing dislocation.

The study found that the cross-sectional area of the femoral tunnel aperture increased by 41.1% over one year, with significant anterior migration of the tunnel, particularly influenced by patella alta, but not by other assessed risk factors.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

3D Computed Tomography Evaluation of Morphological Changes in the Femoral Tunnel After Medial Patellofemoral Ligament Reconstruction With Hamstring Tendon Graft for Recurrent Patellar Dislocation. Kita, K., Tanaka, Y., Toritsuka, Y., et al.[2018]

References

1. United States pubmed.ncbi.nlm.nih.gov

Failure Analysis in Patients With Patellar Redislocation After Primary Isolated Medial Patellofemoral Ligament Reconstruction. [2022]

2. United States pubmed.ncbi.nlm.nih.gov

A Simple Method of Measuring the Distance From the Schöttle Point to the Medial Distal Femoral Physis With MRI. [2022]

3. United States pubmed.ncbi.nlm.nih.gov

MRI evaluation and complications of medial patellofemoral ligament reconstruction. [2022]

4. Germany pubmed.ncbi.nlm.nih.gov

Analysis of failure and clinical outcome after unsuccessful medial patellofemoral ligament reconstruction in young patients. [2022]

5. China pubmed.ncbi.nlm.nih.gov

[Reconstruciton of medial patellofemoral ligament (MPFL) for the treatment of recurrent patellar dislocation]. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

The Medial Patellofemoral Ligament Is a Dynamic and Anisometric Structure: An In Vivo Study on Length Changes and Isometry. [2020]

7. Italy pubmed.ncbi.nlm.nih.gov

MPFL reconstruction: indications and results. [2023]

8. United States pubmed.ncbi.nlm.nih.gov

Dynamic Simulation of the Effects of Graft Fixation Errors During Medial Patellofemoral Ligament Reconstruction. [2020]

9. United States pubmed.ncbi.nlm.nih.gov

3D Computed Tomography Evaluation of Morphological Changes in the Femoral Tunnel After Medial Patellofemoral Ligament Reconstruction With Hamstring Tendon Graft for Recurrent Patellar Dislocation. [2018]